Ventilating device



SePtl'7, 1929. L. J. ocoNNoR 1,728,768

Leo J. 0 "Connor Sept 17, 1929. L.. J. @CONNOR` 1,728,768

VENTILATING DEVICE Filed Sept. 26, 1928 2 Sheets-Sheet 2 nwnfof,

Leo J. OConnor dft@ z ne q Patented Sept. 17, 1929 UNITED STATES PATENTOFFICE LEO J'. OCONNOR, OF CANTON, OHIO, ASSIGNOR 0111"I ONE-FOURTH TOWILLIAM ISLER,

' 0F CANTON, OHIO VENTILATING DEVICE Application led September 26, 1928.Serial No. 308,556.

This invention relates to Ventilating devices capable of permittingeither' forced or natural flow of air through a conduit.

The invention is illustrated as applicable to the cold air inlet pipesof hot air furnaces, but it .may also be utilized in connection withexhaust or inlet stacks and other conduits wherein it is desirable topermit an air flow under natural conditions in accordance withwell-known laws of physics, or stimulate the air flow by artificialmeans, as conditions may require.

`When the usual fan in the cold air inlet to a hot air furnace is not inoperation, the flow of air by gravity to the hot air chamber of thefurnace is seriously impeded due to the obstruction offered by the fan.Various remedial devices have heretofore been proposed, illustrative ofwhich is the patentto Miles 1,508,813, granted September 16, 1924. lt isa purpose of the present invention to eliminate dampers, which are notalways reliable in action, and to provide a simplified and economicalconstruction whereby power means situated in a conduit may be utilizedto supplement the natural flow of air, but which when out of operationwill not impede the natural flow of air.

Wore speciticallv, it is an object of this invention to provide in aconduit a collapsible fan for forcing air therethrough, whereby when thefan is idle and in collapsed condition, a minimum obstruction is offeredto the free or natural flow of air.

Other objects and attendant advantages will be later on referred to orbecome obvious from the following detailed description of one chosenpractical embodiment of my invention; but it is to be understood thatthe same is by way of example only.

In the further disclosure of thisinvention, reference is had to theaccompanying drawings, constituting a part hereof, wherein:

Fig. 1 is a perspective view of thevreturn or cold air pipe o f a hotair furnace, parts being broken away for clearness of illustration;

Fig. 2 isa fragmentary view similar to Fig. 1, showing the fan incollapsed inoperative condition; i

Fig. 3 is a side elevation of the motor driven fan unit in inoperativecondition; only two of the fan blades being shown, for clearness;

Fig. 4 is a similar view showing the fan in operating condition;

Fig. 5 is a fragmentary front elevation showing the blades operativelymounted on the carrier;

Fig. G is a detail view of the collar;

Fig. 7 is a diagrammatic front elevation showing the fan blade assemblywhen the fan is in collapsed condition.

In the drawing I have illustrated a motor driven fan unit designatedgenerally as 10, mounted in the return or cold air inlet pipe 11 leading-to a conventional hot air furnace fragmentarily shown at 12. Theconduit 11 as shown .is substantially vertical, but it is to be notedthe invention in practice is readily applicable to horizontal or otherinlet pipes.

The fan unit 10 comprises an electrically driven motor 13 of anypreferred type secured centrally within the conduit through therinstrumentality of brackets 14 having feetv 15 secured by any suitablemeans to the motor and conduit respectively.

Referring to Figs. 3 to 5, there is shown the usual projecting motorshaft 16. Terminally mounted on the shaft 16 is a. blade carrier 17having boss 18 by means of which the carrier 17 may be iiXedly securedto the shaft as by pin 19 passing through the boss and shaft, see Fig.5.

Formed upon the carrier 17, as shown, are equi-spaced ears 20 arrangedin pairs, having aligned. openings 21 for the reception of pivot pins 22for pivotally mounting blade carrier arms 23 between each pair ofrespective ears. Rigidly secured to each arm 23 is a fan blade 24.Rearwardly offset on arms 23 are spa-ced' ears 25, to which arepivotally secured, asat 2G, terminal portions of links 27.

Loosely and slidably mounted on shaft 1G is a collar 28 having spacedpairs of ears 29 provided with aligned openings 30 for the pivotalconnection of the other ends of links 27, as at 31.

Surrounding shaft 16 is a coil sprin 32 having one end abutting a washer33, w ich vie is free to'slide on the shaft, but the inward movement ofwhich is limited by acotter pin 34 or the like. The other end of thecoil spring 32 is in free abutting engagement with the collar 28. It isworthy of note that when the motor is idle, the collar 28 is forcedoutwardly under the action of the spring, as shown in Fig. 3, withA theresultant swinging of the blades to the collapsed position.

When the motor is started, the centrifugal action on the blades willcause them to assume the operative position shown in Figs l and ll,which position will be maintained so longl asvthe motor isoperating, thetensionlof the spring 32 when under compression as inFig.

i being insuiicient to overcome the centri-fugal force' to which theblades are subjected.

It will be noted that the portion of the conduit housing the fan unit 10isof enlarged cross-sectional area, I this. enlargement being sufficientto rcompensate yfor the slight obstruction to the free lowof.t airoffered by the unit'when idle,'thus insuring free flow of airv whenoperating under natural or gravity dow. I y

,The operation will be apparent from 1the foregoing. When the fan isidle, it is automatically collapsed due to action of the spring, andwhen this position offers a minimum obstruction to the free or gravityiow of air, this slight obstruction being compensated for by the slight.enlargement of the conduit at this point. When it is desirableto operatethe furnace under forced draft, the fan automatically assumes operativeposition upon starting of the motor.

The invention is susceptible of various modifications, as forexample, amanually collapsible fan unit may be employed, or a noncollapsible fan'Whose blades may be individually pivotally mounted forpositioningparallel to the air flow to offer a minimum obstruction when idle,Without departing from the spirit of the invention.

I claim:

l. In an air circulating device, the combination of an air conduit, adriven fan in said conduit, and means whereby said fan is collapsed Whenidle to permit natural air flow through the conduit.

' 2. The structure defined in claim 1, wherein said conduit includes anenlarged portion,

5 said fan being positioned Within said portion,

for the purpose described.

3. In an air circulating device, the combination of an air conduit, adriven fan in said conduit, and means automatically collapsing said fanwhen operation is ceased to permit natural air flow through the conduit.

Il. In an air circulating device, the combination with an air conduit,of a driven fan in said conduit, and means collapsing said fan when idleand permitting automatic return to operative position when said fan isoperated.

1,7ae,ves

5. In an air circulating device, the combination with an air conduit, ofa driven fan in said conduit, said fan being self collapsing when thefan is idle and self opening'when the fan is operated. whereby normalair flow through theconduit is permitted when the fan is idle.v

6. In an air circulating device, the combi nation of an air conduit, adriven fan therein and resilient means to collapse said fan when idle,whereby to permitnormal dow or air through the conduit.

l 7. In combinationwith an air conduit, a driven fan therein, the'blades of said fan ben ing' pivotally mounted, .spring actuatedseliacting means collapsing said blades about said pivots when the Afanisfidle, said last means permitting return of said blades to op erativeposition by centrifugal action when the fan is started. A 8. In an aircirculating device, the combination of an air conduit, a driven shaft insaid conduit, fan blades pivotally secured on said shaft and occupying aposition substantially perpendicular to the axis of the shaft when thelatter is running at normal speed, and means for collapsing the bladesto a position substantiallyparallel with the axis of the shaft when thespeed of the shaft has fallen below a predetermined minimum.

9. A structure as delined in claim 8, in which the last-named meanscomprises a coil spring.

10. In'an air circulating device, the combination of an air conduit, adriven shaft in said conduit, a fanv blade carrier secured to saidshaft, fan blades pivotally secured to said carrier and occupying aposition substantially perpendicular to the axis of the shaft when thelatter is running at normal speed, and means mounted on said shaft forcollapsing the blades to a: positipn substantially parallel With theaxis of the shaft when the speed of the shaft has fallen below apredetermined minimum.

11. A structure as dened in claim 10, in which the last-named meanscomprises a coil spring. l

In testimony whereofI aiix my signature.

